将JSON数组从Server API请求转换为Retrofit2中的对象

Question

I have a server where I query to get a list of topics in a forum. The data returned via curl is something like this -

[
  {
    "id": 728,
    "date": "2016-01-01T13:01:51",
    "date_gmt": "2016-01-01T07:31:51",
    ....
  },
  {
    "id": 556,
    "date": "2015-06-07T21:16:59",
    "date_gmt": "2015-06-07T15:46:59",
    ....
  },
  {
    "id": 554,
    "date": "2015-06-07T21:16:28",
    "date_gmt": "2015-06-07T15:46:28",
    ....
  }
]

Here every JSONObject is a data about forum topic.

{
  "id": 554,
  "date": "2015-06-07T21:16:28",
  "date_gmt": "2015-06-07T15:46:28",
  ....
}

I want to display this data in a ListView in an Android app.

However, since I am using retrofit2 and gson to create the objects for the ListView , the response I always get is Not Found .

Retrofit retrofit = new Retrofit.Builder()
        .baseUrl(ENDPOINT)
        .addConverterFactory(buildGsonConverter())
        .build();

serverAPI = retrofit.create(ServerAPI.class);

private Converter.Factory buildGsonConverter() {
    return GsonConverterFactory.create();
}

Call<List<Forum>> call = App.serverAPI.getListOfForums();
call.enqueue(new Callback<List<Forum>>() {
    @Override
    public void onResponse(Call<List<Forum>> call, Response<List<Forum>> response) {
        Log.i(TAG, "onResponse: " + (null != response.message() ? response.message() : ""));
        Log.i(TAG, "response body - " + (null != response.body() ? response.body() : ""));
        if (response.isSuccessful()) {
            adapter.setForums(response.body());
            adapter.notifyDataSetChanged();
        }
    }

    @Override
    public void onFailure(Call<List<Forum>> call, Throwable t) {
        Log.i(TAG, "onFailure: " + t.toString());
        Log.i(TAG, "onFailure: " + t.getMessage());
    }
});

ServerAPI.class - 

@GET("/forum/")
Call<List<Forum>> getListOfForums();

Right now I am not doing anything when deserializing the returned JSON . Even if I use a JsonDeserializer , how should I go about it such that it is easier to populate the List<Forum> .

Answer 1

You dont need to change JSON itself.

public interface ServerAPI {
   @GET("/forum")
   Call<Forum> getListOfForums();
 }

FormResponse.java

public class ForumResponse {
  @SerializedName("id")
  private int id;

  @SerializedName("date")
  private String date;

  @SerializedName("date_gmt")
  private String date_gmt;
}

---

onResponse in MainActivity.java

@Override
public void onResponse(Call<Forum> call, Response<Forum> response) {
    String jsonString = response.body().toString();
    Log.i("onResponse", jsonString);
    Type listType = new TypeToken<List<ForumResponse>>() {}.getType();
    List<ForumResponse> yourList = new Gson().fromJson(jsonString, listType);
    Log.i("onResponse", yourList.toString());
}